Re: gEDA-user: PCB pin hole size

[Dan McMahill <dan@xxxxxxxxxxxx>]

On Sun, Jan 30, 2005 at 01:14:15PM -0800, Daniel J Wisehart wrote:
> On Saturday 29 January 2005 06:08, Dan McMahill wrote:
> > On Fri, Jan 28, 2005 at 04:19:23PM +0100, Wojciech Kazubski wrote:
> > > > > Shold the specified diametr be the drill size or finished hole size?
> > > >
> > > > My fab shop says drill sized are ALWAYS finished size.  Only the fab
> > > > shop knows how thick their plating is.
> > >
> > > So the footprint creation guide should contain a notice that:
> > > 1) symbols submited to pcb should have diametr of finished holes
> > > 2) if fab shop requires drill sizes, it is up to user to enlarge all
> > > plated holes by specified amount.
> > >
> > > BTW: What sizes of holes are in use in US?
> >
> > see http://pcb.sourceforge.net/pcb.html#Standard-Drill-Sizes
> >
> > I added a big appendix to the manual which lists standard
> > drill sizes.  Its only in the cvs version of the manual, not
> > the last snapshot.
> 
> That is a list of all of the standard available drill sizes, which is much 
> more than any board manufacturer can support.  Here is list of drill sizes 
> you can use with a board built by PCBExpress: 
> http://www.pcbexpress.com/technical/tool.php#drill. 
 
Of course its much more than you'd want to use, but each vendor will have
its own prefered list.  Hence the vendor resource file feature of pcb!

-Dan

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